1. Field of the Invention
The present invention relates to a power system management device and a method which manage a system state to assist an operation of a power system.
2. Description of the Related Art
It becomes difficult to stably control a power system when an enormous amount of natural energy, which generates a steep power fluctuation caused by changes of a climate and an environment, is introduced in the power system. Also, when a large number of devices which control the fluctuation are introduced in the power system, a control structure becomes more complicated. Also, the control fitted to characteristics of the plurality of control devices becomes more difficult. Further, due to a change of a business system such as an electric power deregulation and unbundling generation and transmission services, it becomes more difficult to collectively control and manage the power system, because a plurality of business operators manages and operates the power system.
For the above business operator who operates the power system, an optimized control technique to stabilize the system has been devised. For example, JP-2007-110809-A discloses a support system and a support method for determining a condition in which a distributed power supply is interconnected with a distribution network. In the condition above, when the distribution network, which is interconnected in a branched (radial) shape, is interconnected with the distributed power supply, a quality of the electric power supply is stabilized. Also in the condition above, an applicant who wishes to be interconnected with the distributed power supply is satisfied (for example, to introduce as much power as possible). Disclosed is a method for calculating a tap position pattern in which the number of tap switching of a distribution transformer placed in a distribution substation and a weighted sum of a square sum of a power variation margin becomes the smallest. This calculation is performed under the restriction in which a voltage of the distribution network which is interconnected with the distributed power supply is kept within an allowable range.